The present invention relates to large, xe2x80x9csquarexe2x80x9d hay balers that pick up windrowed crop materials from the field and pass the stream of materials through an onboard rotary cutter apparatus to reduce the materials into smaller pieces before charging the materials into the main baling chamber for compression into a finished bale.
Several different companies currently offer big square balers that utilize onboard cutter apparatus to reduce the inflowing crop into smaller pieces. Typically, such balers are xe2x80x9cin-linexe2x80x9d, bottom-fed machines in which crop material is picked up directly underneath and slightly ahead of an overhead, fore-and-aft baling chamber containing a reciprocating plunger. Successive charges of material are delivered to the chamber through an underslung transfer duct. The cutter apparatus is located generally between the pickup and the transfer duct, and the rotor of the apparatus is used not only to reduce the materials into smaller pieces, but also to feed the materials so reduced into the duct for subsequent stuffing up into the baling chamber by stuffer mechanism operating through successive operating cycles.
A problem with conventional balers of this type resides in their reliance on the cutter rotor as a means of both cutting the materials into smaller pieces and then those materials into the transfer duct to form a charge before the charge is stuffed up into the baling chamber. While the rotor may perform its cutting operations well, it is not particularly suited for feeding and packing. Consequently, the charge may not be well-shaped before being loaded into the baling chamber, with the result that the overall shape of the finished bale may suffer.
Accordingly, one important object of the present invention is to provide improved bale shape in a baler that employs a cutter to cut the inflowing stream of crop materials into smaller pieces before charging the materials into the baling chamber. In a baler according to the present invention, a separate packer is utilized immediately behind a cutter rotor to take the crop materials from the rotor and pack them into one end of the transfer duct. The charge that is thus formed within the duct is subsequently stuffed up into the baling chamber to be compressed into a finished bale in the usual manner. The stuffer of the machine may be provided with control mechanism that temporarily suspends operation of the stuffer in the event the charge being formed in the duct has not reached a predetermined density by the start of the next successive stuffing cycle.
The packer is preferably in the nature of a plurality of packing forks arranged on a crankshaft in such a manner that the forks sweep down through the cut crop materials in staggered secession across the width of the duct. In the preferred form of the packer, teeth sweep down between laterally spaced blades of the cutter rotor as the blades are sweeping upwardly, thus effectively stripping the rotor and positively feeding the cut materials on into the duct in a long packing stroke leading from the cutter rotor to a location deep inside the duct.